The distance between ancient Rome and ancient China was about 40000 miles by land. There were terrible deserts and high mountains on the way. It was a very dangerous trip.

For a very long time, the ancient Romans did not know who was making this wonderful cloth called silk. The Romans first discovered pieces of silk in the goods they took from some of dead people they had conquered (征服). But those people did not know where the silk was made. They only traded for the silk.

The Romans tried to find more traders as they came into villages to trade silk for other goods. But the traders did not know who made the silk either. In fact, the trading along the Silk Road was a relay (接力) system. One trader would travel for a while, stop and trade, and return home. The next trader would continue, stop and trade, and return home. And so it went. No trader made the whole trip because the trip was too dangerous.

As silk was becoming more and more popular, the need for it in ancient Rome had grown. Ancient Rome had treasure. They hoped to find “The silk People” to trade for more silk. But most never returned because they could not make it through the desert. They had to turn around and come back. This went on for a very long time.

As the years went by along the Silk Road, temples appeared. There were even cities built on the oases (绿洲). It was never easy to travel by land from ancient China to ancient Rome. But it was worth it. Ancient Rome traded treasure for ancient China’s silk and spices. In fact, more things travelled along the Silk Road than traders and goods. Ideas travelled along the Silk Road as well. The ideas changed the world.

Did you have a good sleep last night? March 21 is World Sleep Day. It’s a good time to think about our sleeping habits and get more sleep.

Sleep is important because it gives our bodies time to recover (恢复) from the stress (压力) of living.

But today, heavy stress and the habit of using smartphones before bedtime have made people lose sleep, according to the World Health Organization.

About 62 percent of adults (成人) worldwide feel that they don’t sleep well, according to 2019 Philips Global Sleep Survey. In China, around 50 million to 60 million people suffer from (遭受) sleep problems. Losing just one or two hours of sleep per night can affect (影响) us.

“If you don’t get enough sleep at night, you might sleep in school. If you’re asleep, you don’t learn anything,” said Mary Carskadon, a sleep researcher at Brown Medical School.

How much sleep do you need? That depends on how old you are. The Sleep Foundation says that teenagers need 8.5 to 9 hours a day.

How to sleep well?

Having good sleep habits is important. Stop using digital devices (电子设备) for at least an hour before sleep.

Try to go to sleep and wake up at the same time every day, even on weekends and during holidays.

Relax before bed each night by listening to soft music.

To-wit-to-woo. to-wit-to-woo! What’s that strange sound coming from the forest in the moonlight? It’s an owl (猫头鹰), of course!

All day long, seated comfortably on a tree, the owl is sleeping or at least he’s trying to snooze, because it’s sometimes hard to close the eyes with all the sounds made by the little birds and animals in the forest! The owl hunts (捕猎) only at night. When evening comes, the animals all get to a safe place. The owl opens its big, round eyes. Any little animal around had better watch out! The owl mostly eats small animals like mice, but it wouldn’t say no to another bird, if it gets the chance!

The owl uses its fantastic hearing to find its food, and then it turns its head from side to side, using its sharp (锐的) eyes to follow the animal. Finally, it flies down to get the animal. Owls have special, soft feathers (羽毛), so they can fly without making any sound. Owls are such good hunters that they can even catch a fly in the air!

The owl is quiet most of the time, except when you get too close to its home. The owl is a great mother, who will protect her babies by opening her feathers angrily. An owl will even hurt people if she thinks her babies are in danger!

An owl has no teeth, so it eats an animal whole. All the parts of the animal that the owl can’t digest (消化) will end up as small pieces. If you find these small pieces, you know you are near an owl’s home.

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